1. Field of the Disclosure
The present disclosure relates to a charging device of an air circuit breaker , and particularly, to a charging device of an air circuit breaker having a rotation support device capable of preventing a worm gear from being shaken when the charging device is driven and preventing thermal damage due to rotation of the worm gear.
2. Background of the Disclosure
In general, an air circuit breaker (ACB) is a device in which a stationary contactor and a movable contactor, which is movable to a closing position in which the movable contactor contacts the fixing contactor to close a conducting circuit and to a breaking (trip) position in which the movable contactor is separated from the stationary contactor to open the conducting circuit, are always contacted to allow a current to flow, and when an overcurrent occurs due to failure of a line, the movable contactor is rapidly separated from the stationary contactor to cut off current to protect an internal circuit and components within an electronic device form the overcurrent, and in order to extinguish an arc generated at this time, both contactors are exposed in the air and compressed air is provided.
The air circuit breaker has an operating device capable of rapidly breaking/separating contacts of the stationary contactor and the movable contactor, and a driving method of the operating device includes a manual operating method, a solenoid operating method, and an electric spring operating method.
Referring to the electric spring operating method, generally, a closing spring is coupled to one side of a cam shaft in which a charging cam contacting a link connected to the movable contactor is installed and a charging device for rotating the cam shaft using an electric or manual operating lever using a motor is connected to the cam shaft, whereby the cam shaft is rotated in a state that main energy for adding rotation moment is charged to a closing spring to the maximum level using the charging device, and, if necessary, a lock is released and the cam shaft is rotated by energy from the compressed closing spring to sequentially operate a link to separate the movable contactor from the stationary contactor to cut off a current.
Meanwhile, FIG. 1 is a perspective view illustrating a conventional air circuit breaker, FIG. 2 is a cross-sectional view illustrating a charging device provided in the conventional air circuit breaker, and FIG. 3 is another cross-sectional view illustrating a charging device provided in the conventional air circuit breaker.
As illustrated in FIGS. 1 to 3, the charging device provided in the conventional air circuit breaker includes a driving motor 11 and a charging gear module 13 having a plurality of gears connected to the driving motor 11 and rotated according to driving of the driving motor 11.
The charging gear module 13 includes a worm gear 13a connected to the driving motor 11 and rotated according to driving of the driving motor 11, a worm wheel 13b positioned to be adjacent to the worm gear 13a and engaged with the worm gear 13a so as to be rotated, a spur gear (not shown) connected to the worm wheel 13b through a rotational shaft, a first charging gear unit 13c rotated according to rotation of the spur gear, and a second charging gear unit 13d and a planetary gear 13f. When a mechanism shaft (not shown) driving a closing spring (not shown) is rotatably connected to a shaft 13e penetrating through the second charging gear unit 13d and the planetary gear 13f and the shaft 13e is rotated according to rotation of each gear, the mechanism shaft rotates in association to drive a mechanism to compress the closing spring.
Here, one end of the worm gear 13a is connected to the driving motor 11, and the other end of the worm gear 13a is inserted into a rotation support device 15 to prevent shaking when the worm gear 13a is rotated.
However, since the rotation support device 15 provided in the air circuit breaker 10 is positioned such that the warm gear 13a is inserted within a housing forming the rotation support device 15, excessive rotation of the worm gear 3a may cause significant shaking to generate significant vibrations and noise in the charging device.
Also, when the worm gear 13a is excessively rotated, an external housing of the rotation support device 15 may be damaged by heat generated through rotation of the worm gear 13a, and due to the damage, malfunction frequently occurs when the charging device is driven.